4-Ethyl-2',3'-difluor-4''-propyl-1,1':4',1''-terphenyl

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2014-02-21 - 2014-02-27

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient - HPLC Method)

Version / remarks:

European Commission Regulation (EC) No. 440/2008

Deviations:

no

GLP compliance:

no

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

> 6.5

Temp.:

25 °C

pH:

ca. 6

Remarks on result:

other: log Pow 8.3 via extrapolation

Preliminary visual estimation of the water solubility

Different amounts of the test item and water were stirred at room temperature until the mixture

appeared dissolved or the water solubility could be estimated to be below 10 mg/I.

 

Table 1: Results of the preliminary visual estimation of the water solubility

Amount of the test item in mg	Total volume in ml	Appearance of mixture
7.8	100	undissolved
20.1	500	undissolved
4.9	500	undissolved

 

The solubility of the test item in water was found to be below 9.8 mg/I (without correction of the

purity).

 

Preliminary visual estimation of the n-octanol solubility

Increasing amounts of the test item were stirred with defined volumes of n-octanol at room temperature and visually checked for any undissolved parts.

 

Table 2: Results of the preliminary visual estimation of the n-octanol solubility

Added amount of test item in mg	Amount of test item (total) in mg	Added volume of n-octanol in ml	Volume n-ocatnol (total) in ml	Stirring time	Appearance of mixture
29.0	29.0	10	10	50 min	dissolved
56.1	85.1	--	10	120 min	dissolved

 

The solubility of the test item in n-octanol was found to be > 8.5 g/L (without correction of the purity).

 

Calculation of the partition coefficient log Pow

The partition coefficient Pow may be estimated from the saturation concentrations in n-octanol and water by the following equation:

 

P_OW=C_S^octanol / C_S^water                                       (1)

c_s = saturation concentration in g/l.

 

With the data obtained in chapter 4.5.1 and 4.5.2 the partition coefficient was calculated as: log Pow > 5.5. Also the program KOWWIN (part of EPI Suite) was used for calculating the log Pow of the test item. The calculated value was 8.5 for the test item. Therefore the partition coefficient n-octanol/water of the test item at room temperature was determined by the HPLC-method.

HPLC method

The results from the HPLC method are summarized in Table 3 to Table 5.

 

Table 3: Determination of the dead time t0

Dead time marker	tR/min 1st injection	tR/min 2nd injection	tR/min 3rd injection
Formamide	2.42	2.42	2.42

 

Dead time: t0 = 2.42 min

 

Table 4: Calibration data 1st injection

Calibration substance	Inj tR/min	2 Inj. tR/min	mean tR/min	k	Log k	Log Pow
2-Butanone	2.68	2.70	2.70	0.11	-0.95	0.3
Acetanilide	2.71	2.72	2.71	0.12	-0.92	1.0
Cinnamyl alcohol	2.86	2.87	2.87	0.18	-0.74	1.9
2,6-Dichlorobenzonitrile	3.19	3.19	3.19	0.32	-0.50	2.6
Allyl phenyl ether	3.73	3.74	3.73	0.54	-0.27	2.9
Benzophenone	3.55	3.55	3.55	0.46	-0.33	3.2
Cumene	4.90	4.91	4.91	1.02	0.01	3.7
Diphenyl ether	4.54	4.54	4.54	0.87	-0.06	4.2
Fluoranthene	6.74	6.75	6.74	1.78	0.25	5.1
4,4'-DDT	8.10	8.10	8,10	2.34	0.37	6.5

 

Regression: logPow = a+ b · log k

Parameters: a=4.36, b = 3.86, r2=0.9482

 

Table 5: Log Pow of the test item 1st injection

	Inj. TR/min	Inj.TR/min	Mean tR/min	k	Log k	Log Pow
Test item	27.54	27.62	27.58	10.39	1.02	>6.5

Within two injections, the partition coefficient Pow of the test item was determined to be: log Pow >6.5

Conclusions:

The partition coefficient n-octanol/water of the test item was determined according to the HPLC method. It was found to be: log Pow >6.5

Executive summary:

A study was conducted in accordance with OECD TG 117 and Regulation (EC) No 440/2008 method A.8 to determine the partition coefficient of the test substance using the HPLC method. The n-octanol/water partition coefficient of the test substance was derived from its retention time and the calibration graph. The retention time of the test item was above the retention time of the highest calibration standard and thus out of the calibration range. Therefore, the partition coefficient n-octanol/water of the test substance was determined to be above The partition coefficient n-octanol/water of the test item was determined according to the HPLC method. It was found to be: log Pow >6.5.

Description of key information

The partition coefficient n-octanol/water of the test item was determined according to the HPLC method. It was found to be: log Pow >6.5

Additional information

A study was conducted in accordance with OECD TG 117 and Regulation (EC) No 440/2008 method A.8 to determine the partition coefficient of the test substance using the HPLC method. The n-octanol/water partition coefficient of the test substance was derived from its retention time and the calibration graph. The retention time of the test item was above the retention time of the highest calibration standard and thus out of the calibration range. Therefore, the partition coefficient n-octanol/water of the test substance was determined to be above The partition coefficient n-octanol/water of the test item was determined according to the HPLC method. It was found to be: log Pow >6.5.